1. Field
One embodiment of the present invention relates to an electronic device equipped with a loop heat pipe for cooling a heat generating part, a cooling device and a loop heat pipe.
2. Description of the Related Art
For example, Japanese patent application, Jpn. Pat. Appln. KOKAI Publication No. 11-190596 discloses a loop-shaped flat-type heat pipe having the following structure. This loop heat pipe includes a box-shaped container inside which a groove wick is provided, a recessed wall recessed in the vicinity of a central portion of the container and brought into contact with an opposing wall and a working fluid injected in the container. The recessed wall has a length shorter than an effective length of the container. With this structure, the inside of the container is formed to have a loop shape. In this heat pipe, the working fluid is nucleate-boiled in the heat receiving section to form vapor bubbles and at the same time, pressure oscillatory wave is generated. All of the vapor bubbles which have taken latent heat are expanded and contracted by the pressure oscillatory wave and gradually move towards the heat radiating section. Due to the movement of the vapor bubbles, the heat transport is carried out.
However, the conventional heat pipe described above takes such a structure that vapor bubbles are transported by pressure oscillatory wave, which has a low heat transport efficiency. Further, a gas phase portion of the working fluid and a liquid phase portion thereof are allowed to pass through the same path. With this structure, the heat of the gas phase portion of the working fluid is transmitted to the liquid phase of the liquid, and thus a part of the heat being transported is in some cases returned to the heat receiving portion, thereby lowering the efficiency of the heat transport.